Measurable residues of organochlorine pesticides, polychlorinated biphenyls
(PCBs), polybrominated biphenyls (PBBs), polychlorinated dibenzodioxins
(PCDDs), and polychlorinated dibenzofurans (PCDFs) are present in human tissues worldwide (Mes et al., 1982, 1986; Ahmad et al., 1988; Patterson et al., 1988; Thoma et al., 1990; Schecter, 1991; Sasaki et al., 1991). These contaminants share similar physical and chemical properties such as low vapor pressure, chemical stability, lipid solubility, and a slow rate of biotransformation and degradation. Because of these same properties, they also persist in the environment, bioaccumulate, and biomagnify within various food chains and food webs to eventually reach measurable concentrations in human tissue.
This chapter is a synthesis of reports from the last decade on concentrations of
organochlorine contaminants in human reproductive tissues, adipose tissue, and
blood from the general population worldwide, excluding industrial exposure
(Table 1). Special consideration is given to human breast milk fat concentrations
of those chemicals that have been shown to disrupt the endocrine system in vivo
(Table 2). This chapter also focuses on recent findings of transgenerational health
effects, expressed as loss of function that are not obvious and are difficult to
measure in offspring of exposed adult animals and humans.
The purpose of this chapter is threefold: first to provide evidence that humans are
exposed to chemicals capable of disrupting the endocrine system; second to
demonstrate that each endocrine disrupting chemical appears to have its own mix
of mechanism(s) of action and unique target sites; and third to provide insight
into the difficulty of interpreting what exposure to these chemicals means. Only
recently have researchers begun to understand the effects of these chemicals on
functionality and have begun to develop parameters for measuring the results of
parental exposure in offspring. It is this literature that this chapter reviews.
